International immunopharmacology
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Int. Immunopharmacol. · Dec 2013
Nicotine effect on inflammatory and growth factor responses in murine cutaneous wound healing.
The aim of the current study was to investigate the effect of nicotine in an experimental mouse model of cutaneous injury and healing responses, during the inflammatory phase of repair. Nicotine injection in full-thickness excisional skin wounds minimally affected inflammatory mediators like TNF, IL-6 and IL-12 while it induced a down-regulation in the expression of growth factors like VEGF, PDGF, TGF-β1 and TGF-β2, and the anti-inflammatory cytokine IL-10. Analysis of wound closure rate indicated no significant differences between nicotine and saline injected controls. ⋯ Moreover, nicotinic acetylcholine receptor (nAChR) subunit expression analyses indicated that while β2 nAChR subunit is expressed in mouse macrophages, α7 nAChR is not. In conclusion, while skin inflammatory parameters were not significantly affected by nicotine, a down-regulation of growth factor expression in both mouse skin and macrophages was observed. Reduced growth factor expression by nicotine might contribute, at least in part, to the overall detrimental effects of tobacco use in wound healing and skin diseases.
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Int. Immunopharmacol. · Nov 2013
ReviewNeutrophil cell surface receptors and their intracellular signal transduction pathways.
Neutrophils play a critical role in the host defense against bacterial and fungal infections, but their inappropriate activation also contributes to tissue damage during autoimmune and inflammatory diseases. Neutrophils express a large number of cell surface receptors for the recognition of pathogen invasion and the inflammatory environment. ⋯ Here we provide an overview of the receptors involved in neutrophil activation and the intracellular signal transduction processes they trigger. This knowledge is crucial for understanding how neutrophils participate in antimicrobial host defense and inflammatory tissue damage and may also point to possible future targets of the pharmacological therapy of neutrophil-mediated autoimmune or inflammatory diseases.
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Int. Immunopharmacol. · Nov 2013
Increased expression of heat shock protein 70 in chronic obstructive pulmonary disease.
Heat shock protein 70 (HSP70) plays a critical role in the process of inflammation and innate immunity response under environmental stress. ⋯ Our study clarified that increased expression of HSP70 is closely related to COPD disease severity and smoking status. Extracellular HSP70 regulated chemokine productions and EGFR phosphorylation and plays an important role in the CSE-induced inflammatory and innate immunity responses in bronchial epithelia cells.
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Int. Immunopharmacol. · Nov 2013
A tetrahydroisoquinoline alkaloid THI-28 reduces LPS-induced HMGB1 and diminishes organ injury in septic mice through p38 and PI3K/Nrf2/HO-1 signals.
We investigated whether THI-28 [1-4-(hydroxyphenylethyl)-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline] inhibits release of high mobility group box 1 (HMGB1), a late phase cytokine of sepsis, in lipopolysaccharide (LPS)-stimulated RAW264.7 cells through heme oxygenase (HO)-1 induction so that it shows beneficial effects in the cecal ligation and puncture (CLP)-induced septic mouse model. Silencing of target genes (HO-1, Nrf-2) or pharmacological signal inhibitors was exploited to investigate the HO-1 induction by THI-28. The dependency of HO-1 by THI-28 on survival rate and circulating HMGB1 level was tested in CLP-induced septic mice. ⋯ Decreasing p-IκBα by THI-28 resulted in inhibition of NF-κB activity which was reversed by silencing HO-1 RNA in LPS-activated cells. Most importantly, increased survival and reduction of liver and kidney injury and circulating HMGB1 levels by THI-28 in CLP-mice were reversed by ZnPPIX, HO-1 inhibitor. Taken together, these findings suggest that the novel compound THI-28 induces the expression of HO-1 by activating the PI3K and p38 MAPK pathways and suppressed HMGB1 and iNOS production in LPS-treated macrophages and septic mice, which may be useful in treating organ injury due to sepsis.
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Int. Immunopharmacol. · Nov 2013
Ulinastatin is a novel candidate drug for sepsis and secondary acute lung injury, evidence from an optimized CLP rat model.
Ulinastatin is a potent multivalent serine protease inhibitor, which was recently found with therapeutic potentials in treating sepsis, and the most life-threatening complication of critically ill population. However, the pharmacological features and possible mechanisms need to be further elucidated in reliable and clinical relevant sepsis models. As known, sepsis induced by surgery of cecal ligation and puncture (CLP) is widely accepted as the gold standard animal model, but the inconsistency of outcomes is the most obvious problem. ⋯ Ulinastatin was also found to be effective in ameliorating sepsis-related ALI, a syndrome most frequent and fatal in sepsis. The molecular mechanism investigation showed that ulinastatin's protection against ALI was probably related to the down-regulation of NF-κB activity and inhibition of TNF-α, IL-6 and elastase expressions in the lung tissue. In conclusion, based on a successful establishment of optimized rat CLP model ulinastatin is proved to be an effective candidate for sepsis treatment, due to its anti-inflammation and anti-protease activities that ameliorate systemic disorders, prevent organ injuries and thus improve the survival outcomes of sepsis in animals.